On my Core I have removed all Audio that I used for testing and added all my 640 albums to public (/home/public/data/audio/Storage1 [27]/Audio). There are also some Audiobooks in my personal home (/home/user_1//home/user_1/data/audio/Storage1 [27]/Audiobook).

I changed the Genre of all Audiobooks to "Audiobook" because they were tagged badly.

Now there is only the old tags of the Audiobooks - and nothing else. See attachment.

Any idea what casued this ? Could someone tell me where in the Database to look for the Genre ?

in the web frontend select "Files & media/Media browser" and set checkbox at Genre, the press "Go". Now press Properties next to the wrong genres. Change the name at the top and press "Update". If the genre is already there it will ask you if you wish to Merge - say YES here. Keep doing that for all geres that are wrong.Now the genres are "merged".